New York ? The last steel beam left standing at the World Trade Center site was cut down Tuesday evening in the first of a series of ceremonies marking the end of the sorrowful, 8 1/2-month cleanup.

The 30-foot girder survived when the twin towers collapsed into a mountain of 1.8 million tons of rubble Sept. 11. For months it was covered by debris, but as the pile shrank the column was revealed, still standing where it was erected when the south tower was built three decades ago.

During the last few months, workers topped it with a flag and covered the sides with spray-painted messages and photographs of victims.

“It means a lot to people it’s like a flag, which is a piece of cloth, but it represents our country and an idea. The idea of the beam is our strength, our resilience,” said Richard Streeter, who has operated an excavator at the site since Sept. 12.

Hundreds of construction workers who have labored at the site watched as the column was severed with a cutting torch.

The ceremony was the first of three planned for construction workers, rescue workers and families in a gradual farewell to the round-the-clock recovery operation.

On Thursday, the beam will be removed from the site in a procession past an honor guard of police officers and firefighters. It will be put into storage and might be used someday in a memorial.

The ceremony, organized by the city, will begin at 10:29 a.m., the moment the second of the towers crumbled.

A Fire Department bell will ring the signal for a fallen firefighter, after which a stretcher with a folded flag will be carried out of the site, honoring the victims whose remains have not been found.

To accommodate those who could not attend the ceremony in the middle of the work week, victims’ families have planned their own service at ground zero on Sunday. The city has issued permits for the event.

Of the 2,823 people killed in the attack, the remains of 1,092 have been identified. But nearly 20,000 body parts have been recovered, and the medical examiner expects to continue identification work for at least eight more months.